Electrically or electromagnetically operated switch valves comprise, inter alia, the components described hereinbelow in more detail. Such a valve comprises in particular a movable structural group with a magnetic armature which is movable along an axis in a valve sleeve, whereby in a first position at least one flow is released which is blocked in the second position. For this, the magnetic armature is coupled to a sealing element which co-operates with a valve seat. The magnetic armature is moved by energizing a coil which surrounds the valve sleeve.
Valves of the above-mentioned kind are used for a great variety of purposes. They are used for example in different ways and for different functions in air suspension systems of automobiles. For example, there are valves for filling and emptying the air spring bellows, valves for connecting or disconnecting accumulators in the system, as well as valves via which the bellows volumes can be connected to additional volume as needed. Preferably, such valves are operated electromagnetically, as is the seat valve described in DE 10 2011 078 102 A1.
The dynamic behavior of the automobile requires a short switching time which entails a high switching speed and impact speed of the movable components or sealing elements. Known valves were hence provided with damping elements which damp the impact of the movable components against the stationary parts. The seat valve described in DE 10 2011 078 102 A1 has, for example, such damping elements which damp an impact of the magnetic armature on a pole member. However, the switching operation of the valve is acoustically perceptible in spite of impact damping elements. Hitherto, this switching noise was concealed by engine noises of the internal combustion engine. This concealment is reduced, however, for example because at present immission control measures, like start-stop automatic system, hybrid drives or electric vehicles are implemented, for the reason of which the switching noise comes to the focus of attention and is audible to the vehicle passengers.